Ingot mold



Jan. 19 1926.

y 1,570,473 E. GATHMANN INGOT MOLD f Filed Oct. 16 1925 I have found that'by employing al shorter a'relatively short concurves, .having suitable radii. "lfhev 'mold shown has.. aA cavity," the I'n'ajorportion-v AApplication liled October 1.6,"1925L Serial No. 62,755. I

To'cZZ whom t may concern.'

Be it-known that I, EMIL GAT'HMANN, v-a citizen of the United States, residing in Baltimore city, State ofvMaryland,-haveinvented certain :new and useful Im rovements in Ingot Molds, Vof which thel ollow ing is a specification.

This invention relates to 'ingot 'molds .of the kind in Awhich the mold chamber has a bottom vopening closedv :by a plug whilev casting and which'isstrip ed or hasvv the ingot removed frome'the mol by forcing the plug into themold cavity sol as to raise the lngot to afsuicient extent-to ermit it to be engaged by lifting devices w ich withdraw it from' the mold. In such molds', the plug not only Yserves as a bottom closure for the mold cavity, but receives the impactof the molten metal while being poured into the molds of the Gath mann ty e, or those 1n which the mold cav.

'der at top than at bottom and gradmold. In big-end-up entire surface, imperfections often occurring here and there/W rich prevent a` close t, of

-the plug in the bottom opening of the mold.

When this is the case the molten metal-often leaks down between the sides of the'opening and the sides of the plug, forming fins whichinterfere with the movement of the plug during stripping and also prevent free contraction of the ingot metal while solidifying, resulting in'cracks in thelower part of the ingot whichnecessitate 'a considerable discard in the bloom'rolled from the ingot.

Generally the bottom opening hasjtapered walls and heretofore it as been -diiiicult .to

robtain exact dimensions of .the plug' relatively to the diameters of the bottom open plug or one havin ltacting surface wit the walls -of the bottom opening, f these objections are. ov

g eater than their `it is provided wit molded wit greater accuracy than where Such a plu -may have its contact. surface I.

the plug is long or has an extended contact f surface. It is of course, important that where the contact surface is relatively small,

some.v means should be provided forgiving the necessary strength to thefplug and ithis vmay be 'done by providing the plug with a bottom portion, the peripheralwall of which is of.` such diameter 'thatv it doesnot come in 'contact with the side walls of thebottoma opening of-the mold, but this lower portion v may bemade sufficiently large, strong ,and 'I0y heavy'to give to the plug as a whole suilicient strength and stabillty to support the molten ymetal and to, receive the impact of A I the molten metal whilebeingfpoured.

In carryincr out my invention I maketh'e. plug much shorter than heretofore, the u per-portionwhich comes in contact with t e walls of the bottom opening being only suficient to seal the opening and the plug as -a whole is made offsuch length that it will stand the im act and pressure of the molten metal. Pre erably the lower portion of the plug is tapered in such manner that its pevriphery is'entirely out of contact with the walls of the bottom o ening but this portion ofthe lug is of suc size and stren h as to rein 'orce the active or sealing lportion of the plug.

In the accompanying drawings:

Figure 1 is a vertical central section of a Gathmann ingot mold with my improvements a plied.

The dliawing also shows a stool on which the moldis supported and a feeder'or shrink head casing through which the molten metal is poured.

Figure 2 is a `bottom plan view of the mold.

Figure 3 is a side eFe'vation of the sealing plug.

Figure 4 is a to plan view thereof.

casing B of 'any suitable kind. In this instance the mold is .of the big-end-up type,

'the bottom of the cavity asl indicated at a'.

The mold is tapered inwardly ybvsuitable 10o 'i The mold A, which as before stated, is'of the Gathmann ty e, rests on a stool S and a feeder or shrink head of which is of general rectangular shape but at the bottom it is necked in so as to properly communicate with a central opening O, which is the bottom opening of the mold and preferably has tapered side walls o as usual. The opening s in the stool is considerably wider than the bottom opening of the mold and when the mold is being stripped, the stripping mechanism preferably operates through the opening s as is well undei'stood in the art.

As before explained, sealing plugs have been heretofore used, but they have been quite long and had quite an extended bearing or contact surface and it has been extremely diilicult to obtain sealing plugs having peripheral contact surfaces which are true and even. This is largely because the plug as a whole is large and heavy and true molding has been difficult. I have found that I can mold with greater accuracy and less expense a plug of relatively small length, that is a plug the length of which is much smaller than its width or diameter. A plug of this description is illustrated in the drawings at P. This plug is more than twice as wide as its length. It has a periph'- eral inclined contact surface atp adapted to it accurately the inclined side walls o or the bottom opening of the mold. The plug is circular in plan as indicated in the drawings because experience has shown that the circular bottom opening for the mold is preferable. A lug having the upper portion with perip eral inclined walls p would seal in a way the tmold, but such a thin plug would not be able to stand the weight of metal or the impact of the metal poured into the cavity, therefore, it has been found necessary to reinforce the plug and this has been done by providing it with a lower brtion p which in this instance is provided with inclined eripheral walls jl/ which have a sharper inc ine than the walls '10, so that the walls y shall not come in c ontact with the side walls of the bottom opening of the mold. The precise dimensions vary with different molds. `Where the bottom opening of the mold is 12 inches in diameter at the top of the opening where it begins to tapeiand this bottom opening is 10%' inches in diameter at the bottom, the diameter of the top of the plug is preferably made 11% inches so that the plug will sink to a short distance within the bottom opening. The peripheral contact surface in the plug shown tapers from a diameter of 11% inches to a diameter of 111/1` inches and the diameter of the reinforcing partp. at its lower end is lOl/z inches. These dimensions give the best results in a mold of'the kind shown having a 12inch diameter bottom ope-ning, ta ering to a diameter of 10% in-ches but t ese `dimensions are` not obligatory, they aro largely relative and are changed consider- 4its lower surface will extend a forced ably lwhen the invention is applied to different kinds of molds.

It will be observed that in the constructionshown the maximum diameter of the plug is somewhat less than the maximum diameter of the bottom opening of the mold in order that the plug shall not project above the top of the bottom opening or into the lower part of the mold chamber. If the plug should project into the mold chamber it would cause a loss of ingot metal due to the inclusion of the plug material in the bottom of the ingot cast and hence lessen the percentage of sound saleable product which may be obtained from the ingot. In other words, if the plug is included in the casting at the bottom of the ingot, it is necessary to crop -just that much of the bottom portion of the ingot which is a loss in manufacture. 'lhe plug isd preferably so dimensioned that the vertical height or tliicknessthereof is such that when the plug is seated in the bottom openin of the mold l ve the bottom ofthe mold. This arrangement prevents an accidental loosening of the plug from its seat in the bottom opening of the mold when the mold as a whole is placed onl a flat solid stool. In other words, the npreferable arrangement is such that the lug when in use shall be seated entirely within the bottom opening of the mold, its lower v end being appreciablyabove the lower end of said bottom opening and its upper end being appreciably below the top of said bottom opening. This arrangement cooperates advantageously with a mold of the kind shown in which the lower ortion of the mold walls are necked-in an in which there is a concavo-convex formation of the walls of the mold cavity or chamber above the top of the bottom opening of the mold.

Another feature of the invention which may be mentioned is that in strip ing the mold there is less friction than wou d be incident to the use of a plug of usual/length and if the plug adheres 'to the ingot when it is stripped, there is less material to be cropped at the lower end of the ingot.

I claim as my invention:

1. A sealing plug for ingot molds formed with a peripheral contact surface, the' diameter of which is materially larger than the len th of the plug, and wliichis ireiiiy a lower portion ot reduced diameter having no. contact surface.

l2. A sealing plug for ingot ,molds having an upper portion formed with an inclined peripheral contact surface, thediamcter of inclined peripheral contact surface, the diameter ol which is materially greater than its length, and a lower tapered non-contacting peripheral portion of less/diameter than the upper part of the plug. y

4. The combination with an ingot mold having a bottom opening, of a sealing plug having an upper portion formed with an inclined peripheral contact surface, the diameter of which is materially greater than its length, and a lower non-contacting peripheral portion of less diameter than the upper part of the plug, the plug as a whole being materially greater in width than in length.

5. The combination with an ingot mold having a necked-in lower portion with' concavo-convex walls and a circular bottom opening with inclined walls, of a sealing plug having an upper portion formed with an inclined peripheral contact surface, the

diameter of which is materially greater than. i

the length of the` plug asa whole, and a lower non-contacting peripheral' .portion of less diameter than the upper part of the plug, the'lower portion of said plug being seated to terminate short of the bottom of the mold opening.

6. An ingot mold having a chamber with a necked-in lower portion provided with concavo-convx walls, and aci-rcula-r bottom opening having inclined walls, in combinat1on with a sealing plug having an upper portion formed with an inclined peripheral contact surface, the diameter of which is materially greater than the length of the plug as a w upper part of the plug.v

Intestimony w ereof, I have hereunto ole, and a lower non-contacting perlpheral portion of less diameter than the` 

